计算圆周率/4,精确到1e-6

在这里插入代码片
#include<stdio.h>
int main(void)
{
 double sum = 0;
 do
 {
  static int i = -1;
  i++;
  double term = 1.0 / (i * 2 + 1);
  if(i % 2 == 0)
  {
   sum += term;
  }
  else
  {
   sum -= term;
  }
  if(term < 1e-6)
  {
   break;
  }
 }while(1);
 printf("%.6f",sum);
 return 0;
 }